Dear all, My colleagues and I are pleased to announce the publication of our paper "Underwater photo-identification of sperm whales (*Physeter macrocephalus*) off Mauritius"in Marine Biology Research. Abstract The long-term monitoring of long-lived animals often requires individual identification. For cetaceans, this identification may be based on morphological characters observable from a boat such as shape, spots and cuts of the back, fluke and dorsal fins. However, for some species such as the sperm whales (*Physeter macrocephalus*), this approach may be challenging as individuals display a rather uniform skin pigmentation. They also do not very often show their fluke, complicating individual identification from a boat. Immature sperm whales that usually have an unharmed fluke may be excluded from photo-identification catalogues. Within the framework of the Maubydick project, focusing on the long-term monitoring of sperm-whales in Mauritius, passive underwater observation and video recording were used to identify long-lasting body markers (e.g. sex, ventral white markings, cut-outs of fins). A catalogue of 38 individuals (six adult males, 18 adult females and 14 immatures) enabled observers to record some nearly-daily, and yearly resightings. Advantages and disadvantages of this method are presented here. Such catalogues represent a robust baseline for conducting behavioural, genetic and acoustic studies in social species. Benefits of such newly acquired knowledge are of primary importance to implement relevant conservation plans in the marine realm. The article can be accessed for free for a limited time via the following link : <https://www.tandfonline.com/doi/full/10.1080/17451000.2022.2040737?src=> https://www.tandfonline.com/eprint/VHRRHWU5WPMDCUBTWWMR/full?target=10.1080/... It can also be access via https://www.tandfonline.com/doi/full/10.1080/17451000.2022.2040737?src= Best regards, Justine Girardet -- GIRARDET Justine Université de Brest, UFR Sciences et Techniques 6 avenue le Gorgeu, 29200 Brest, France Institut de Systématique, Évolution, Biodiversité UMR7205 (ISYEB), Equipe Homologies Muséum National d’Histoire Naturelle, Station Marine de Concarneau justinegirardet@gmail.com 0782424534